This invention relates to medical methods and apparatus, and more particularly to methods and apparatus for installing a tubular graft in a patient for such purposes as bypassing an occlusion or narrowing in the patient's tubular body structure.
The invention is applicable to making anastomotic connections between all body conduits. For example, the invention also has application for attaching coronary artery bypass grafts. Specifically, connection methods and apparatus are provided for attaching the graft ends to the coronary artery and the aortic artery. In the case of the internal mammary artery, connection is required at the coronary artery only.
Conventional coronary artery bypass grafting requires the heart and associated vessels to be accessed through the center of the chest by splitting the sternum (e.g., median sternotomy) or through the side by separating the ribs (e.g., thoracotomy). The heart is typically stopped during this process, and the patient is placed on cardiopulmonary bypass. These procedural steps are typically performed in order to allow the physician to safely and precisely sew the grafts with sutures to the exposed arteries as deemed necessary. However, this procedure may involve risks to the patient attributable to the magnitude of the incision required and the procedure of stopping the heart, which allow the physician the access to stitch on a non-beating heart, i.e., “static” stitching. This procedure may also be associated with various complications, including stroke, heart block, and long patient recovery times. Another factor is the considerable operation time involved due to the criticality of individual hand sewing of each graft end required by the suture process. The precision with which the grafts are sewn may influence the ultimate patency term for the graft.
Typical prior art procedures have been described by Heartport, for example, which attempts to connect vessels through ports inserted between the ribs but also requires the heart to be stopped and the grafts be sewn in place. Cardiothoracic Systems describes a procedure wherein the heart is allowed to beat, but full access to the heart is required as well as hand sewing of the graft segments to the beating heart. Other procedures describe the use of robots and automated mechanical assist devices to complete a sewn anastomosis on beating hearts or through small incisions.
It is thus an advantage of the current invention to overcome some of these difficulties associated with cardiac surgery.
It is an advantage of the invention to eliminate the need to stop the heart.
It is a further advantage of the invention to reduce significantly the size of the incision and to reduce the exposure of the heart and aorta necessary to perform the surgery.
It is still a further advantage of the invention to reduce the time necessary to perform the anastomosis procedure by eliminating the time-consuming task of manually suturing the vessels together.
It is also an advantage of the invention to provide an improved and consistent anastomosis result, without the reliance on the technique and skill of the physician.